The present invention relates to a digital data interfacing system, and more particularly to a data interfacing method and its device for providing a predetermined synchronism to a predetermined magnitude data group transmitted asynchronously with a predetermined data format.
Generally, a video appliance or an audio appliance or the like comprises a data input device for inputting data by a user and a data processing device for processing the input data. There are many systems or subsystems in a system for transmitting the data from a data input device to a data processing device, and the present invention relates to a data interfacing system for processing the digital data transmitted asynchronously in serial form. There are various kinds of data input devices for generating data asynchronously in serial form, such as, for example, a mouse, joy stick, tablet, etc. Since such data input devices can easily draw a figure or pattern, they have come into wide use. In the case of a tablet, when any figure or pattern is drawn on the tablet with an electronic pen, a predetermined data group corresponding to each picture point is produced, and the data of this data group is transmitted asynchronously in serial form. However, since most electronic appliances recognize data exchange only for synchronous data matched to a predetermined clock signal, the asynchronous data of the tablet must be synchronized in order for the data exchange between the tablet and the data processing device to occur. Also, a data processing device requires a process which deletes redundancy data and extracts only necessary data, and an interfacing system for synchronizing the input data is required also for such data processing.
A conventional data interfacing system synchronizes the digital data of a predetermined data group unit transmitted asynchronously in serial form from a data input device, and particular software is used in the data interfacing system for extracting particular data from this synchronized data group. However, in case of carrying out the data interfacing operation by a software system, there have been problems in that the software must be different or changed to be matched to the characteristic of the corresponding appliance in accordance with the appliance for executing the data input and process, and one must always be careful so as not to damage the program. There has also been a problem that there might be a limit on the data processing speed due to the software like data processing system, and thereby it is inconvenient to a user.